<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<title>JS 控制样式示例</title>
<script src="script.js"></script>
 <link rel="stylesheet" href="styles.css">
</head>
<body>
<button id="myButton" class="button-style blue">点击我变色</button>

</body>
</html>